Bob got a call to go to a convention center where the air conditioning system was not working. It was a 75-ton unit with one compressor. The system was many years old, but had been functioning fine, until now. After checking out the unit, an ohm check showed 0 resistance to ground.
The increased use of high pressure refrigerants has created new challenges for technicians, yet it is still possible to perform high speed recovery of high pressure refrigerants. The tips and practices in this article will help keep your refrigerant recovery speeding toward the finish.
Does it make a lot of sense for a commercial HVAC contractor, who specializes in rooftop unit service and replacement, to market his wares on social media networks like Facebook and Twitter? If you had suggested this to Jon Lazarus a few years ago, he might have wanted to find a straitjacket for you. But not now.
Safety is a priority when working on any mechanical equipment, but it is especially heightened when the equipment weighs several thousand pounds and is located on a roof. Some contractors schedule days and weeks on the installation and service for one client alone.
Bob has been sent on a service call where the customer is complaining about her power bill. She thinks that the heat pump may be the problem. Her power bill is much higher than last year. She explained this to Bob and he started by asking a question, “Does the auxiliary heat light come on very often on your thermostat?”
Accurately troubleshooting and repairing refrigeration systems requires technicians to use many specialty instruments. They base many of their diagnoses on what is read from these instruments. Relying on them to be consistently accurate day in and day out is a must. If these tools are inaccurate, more than likely the diagnoses will be inaccurate.
This article is part two of a two-part series on ice flake machine troubleshooting. The last article, which appeared in the Feb. 7 NEWS, examined troubleshooting low and high water levels. This article will examine water impurities and mechanical problems.
Bob and Btu Buddy were on a service call yesterday where the compressor motor was running overloaded due to internal load; the bearings were dragging or worn. Btu Buddy told Bob, “Motor overload protection and circuit protection are subjects that need to be discussed later.” They’ve gotten together today for that discussion.
While repairing refrigeration equipment, technicians sometimes come up with unique methods of solving problems. Many of these are used again and again and become known as “tricks of the trade.” When a bunch of technicians get together, they oftentimes enjoy sharing new tricks they learned or developed recently. It’s like a badge of honor.
My Feb. 7 column focused on ice flake machine troubleshooting. I will have more to say on that specific topic in my April 4 column. For this column, I want to take a look at amperage as it relates to HVACR compressors.